If Miami can catch a break on injuries, especially with Tua, there's a good chance for double-digits wins. My mind says 7, but looking at the schedule Miami could get off to a 6-1 start. It will be interesting to see if Grier adds a corner or if the Dolphins will be relying almost exclusively on unknown talents there.
If there are limited injuries, Tua stays healthy, and McDaniel gets plays in quickly and efficiently (and learns to adjust well), the sky is the limit, IMO.
I do not think all of those things happen, particularly the last one.